Systems for suppression audio distortions become more and more important. Particularly, in the field of high-quality hands-free telecommunication systems such as mobile phones, car kits, audio and teleconferencing systems, hands-free voice recognition devices, etc.
WO 2005/076662 discloses a system which is suited for suppressing audio distortion. The system comprises echo cancelling means coupled between an audio output and a distorted desired audio sensing microphone array, and a filter arrangement coupled to the echo cancelling means and/or the microphone array. The filter arrangement includes filter coefficients representing at least a part of the audio distortion, such as reverberation. The system also comprises an at least partly mirrored circuit arrangement for copying thereby simulated audio distortion representative filter coefficient values into the filter coefficients of said filter arrangement. Such copied values can be then used for suppressing reverberation in a distorted desired signal by the filter arrangement. Such a system and filter arrangement may be suitable to suppress echo distortion in the form of echo tail part reverberation in an audio signal sensed by a microphone array.
However, there may be still a need to provide a system which further improves echo cancellation in an audio system, in particular in a hands-free telecommunication system.